Description:
Harpy's Perch can increase number of pierce targets while builder-player use corrupt form of Dryad.
+1 pierce without sphere , +2 with "Harpy's Pierce" sphere.
But description doesn't changes.
Screenshot:
http://images.akamai.steamusercontent.com/ugc/138878581195663145/3D61DEB9483665D2FAAF2793F03934AE68CFFB08/
That's just inspect visual bug.
Pierces works good.